Ke witt nelson



DE WITT NELSON. TRACTION BELT.

APPLICATION FILED SEPT- ll. 1915.

1,230,504. 7 PatentedJunelE), 1917.

2 SHEET$-SHEET I.

\ lV/f/ress es DE WITT NELSON.

TRACTION BELT.

APPLICATION FILED SEPT|I1I 1915.

1,230,504. Patented June 19, 1917.

2 SHEETSSHEET 2.

Wff/resses: //n e/7f0 r.' M pew/w 449/50 U T D T E PATENT. OFFICE.

DE-W'ITT' NELSON. or MINNEAPOLIS. iviilimnso'm, nssisnon TO TOM THUMB Tiu c'ron COMPANY, or MINNEAPOLIS, MINNESOTA, A CORPORATION.

TRACTION- EL Application filed September 11-, 1915. SerialNo. 50,123.

T 0 all 11171 077141 may concern:

Be it known that 1, DE VITT NELsoN, a citizen; of the United States, residing at l\'linneapolis5 in the county of'Hennepin and State of"l\1innesota, have invented certain new and useful Improvements inTraction- Belts, of which the following is a specification.

My invention relates to traction belts such as are employed in what is known as the of travel is reversed the elements the belt .in contact with the earth are subjected to compression and hence due to their flexibility of attachment tend to buckle away from the earth to such an extent that contact is only secured directly under the wheels, thus decreasing the tractive power of the belt. My invention overcomes this difiiculty by providing the belt elements with interlocking means whereby the same when in a straight position forms a rigid plate such that the compression transmitted to the lower portion of thebelt in traveling back ward may be directly taken up by that por tion of the belt without causing the belt to, buckle, thus securing gripping contactwith the earth along the entire surface of the belt exposed to the earth. This interlocking means on the belt elements is so devised that the members thereof unlock when the belt is travelingabout the wheels, thus providing suitable flexibility for that purpose and suiiicient 'rigidity when it is traveling in a straight line. v

The full objects and advantages of my invention will appear in connection with the detailed description thereof and are particularly pointed out in the claims.

In the drawings, illustrating the application of my invention in one form,

Figure 1 is a plan view of a portion of my improved caterpillar belt showing the same in a straight extended position. Fig. 2 is an elevational view of the parts shown in Specification of LettersjPateiit. IatentedJune 19, 191?],

Fig. 1 with someof them in section; Fig. 3

.is a view similar to Fig. :2 of the belt passiiig over'a portion of-one ot' the pulleys.

Fig. 1 is a transverse section of. the belttaken on line -l1 ot Fig. 1. Fig. Sis-a view similar to Fig.2 with some of the parts in relatively shiftedpositions. Fig. 6 18. 21

elevational view of a inodilicatioii of the device shown in Fig. 5. Fig. '4' is an elevational view of a n'i'odification of the belt shown in Fig 2.

My improved caterpillar belt. as-shownin the preferred form "in. Figs. 1, 3, land 5; comprises a. plurality of transverse slats 10 attached at each end'to a pair of cables 11 and 12 by a like number of clamping blocks 13 and 14 bolted 'thereto.- These clamps are provided with grooves 15 and 16 through which cables 11 and 12 pass, said' gri-iovesbeing kinked at 17 to rigidly gripusaid cables. A bolt -18, integral with block 1e, passes through-block 13, serving to firmly grip tlie'said cables and hold thei i in place. The slats 10,-- as best seen in Fig. 2, are provided with depending fins 19 'for'takii-ig-hold upon the ground and are fastenedto clamp blocks 13 and-14 by means-of bolts 20- passing'througli blocks 1+1 and'by'means of bolts 21 passing through bothblocks 13 and- 1-1. It can thus be seen that suitable means are provided whereby said slats may be readily removed fiom'the belt without disconnecting the sa iie: I

The belt thus described rides at'eacl end upon a. pair of sprocket wheels 22,fsaid sprocket wheels being provided with teeth tended portions 25 of clamp blocksfMa-and through the slats 10, the rim portionof said .23 engaging in holesZal passing through ex- 13 are formed in anarc of a circle t lie'i a diiis of which is equal to the radius off thle lesser sprocket wheel. It hence becomes evident that cables 11 and 12 as the beltlmounts the sprocket wheels recede from groove"1'6 to conform to the outline of grooveslfi. thus allowing the belt to travel oveif said sprocketswithout aflecting the length of the cables and hence insuring a smopthly-ri nning. positively-driven belt.-

Each of clamp blocks 13. as clearly shown in Figs. 1 and 2. is provided with a forwardly-prpjecting hook-like lug 26 at one end thereofandfa similar rearwardly-projecting hook-like 111g 27 at the other end thereof, lug 27 of one clamp bein adapted to engage with 111g 26 of the next 0 am and so on throughout the whole length of the belt, so that when the belt is perfectlystraight the contacts 28 between the hook portions of these lugs are just made and the edges 29' of the lower blocks 14: just touch. This has the effect ofproducing a. rigid plate which can collapse in one transverse direction. The lower portion of the. belt which comes in contact with the ground is hence prevented from receding away .from the ground and so tractive power can the straightenedposition all of the strain is removed from the cables and taken by the individual members. I

Toprevent the belt parts from clog 'ng up with dirt, especially between the ges 29 of clamp blocks 14 as the same close-together in 's'trai' htening outafter leavin the sprocket wheels, a limited later-alshi? ting of the. slats and clamps attached thereto relative to each other is provided, as shown in Fig. 5. The, surfaces of contact 28 of the lugs 26 and 27 are made fiat and perpendicular to the plane of slats 10 so that each lug may slide on the surface 28 in that plane. A portion 30 of. said lugs 26 and 27 s caused to project out beyond the cl-amp block 14 and to engage a portion 31 ofsaid 'clamp block lugs 27-, limiting the upward. mot on, and lugs 26 the downward relative motion of the slats. Both these portionsare rounded so thata binding or catching e-fiect is impossible. When dirt gets between men-ti onedin the preferred form and acts in a .similar manner. This formhas the ad:

- vantage of disengaging when'the belt passes about the sprocket wheels.

Theent setsof hooks 27 and 26, hereto fore described, may be dispensed with by the adoption of the device shown in Fig.1. In this case the ends of the upper clamp blocks 37 are curved at 35 aiidroll against-a washer 36. The natureo'f curve 35 is such that in whatever position the belt maybe the length of the cables 38 between the points or at.-

tachment must be equal. "The lower clamp blocks 39 are left straight at 40 and the device, as clearly shown, is adapted to have lateral collapsibility or bending in onedirection and is adapted to be subjected to compression "in a manner analogous to the method brought out in the preferred form. In this form the cable carries all the tensile stresses, which are taken up'by hooks 26 and 27 in the preferred form.

My invention has unlimited application to devices "for tractive purposes as set forth and may be used in connection with belt conveye'rs and similar devices where a travel'i-ng endless upper surface of rigid character isrequired, thus eliminating undue strain in a line-connecting the axes of S121}?- port and dispensingwith numerous idler supports or the like.

' I claim: I

1. A traction belt for caterpillar type traction engines comprisinga plii rality "of slats, pairs of blocks positioned on said slats, there being grooves in saidblocks, 'a eable passing" through said grooves in thebloc'ks, and means within the grooves cngaging'y'md cableto distort the smear preventing'the slats from sli ping on the ca 1e, and means for securing t e blocks together upon the 2. A traction belt for caterpillar type traction engines comprising a plu -lit'y'of slats, airs of blocks positioned on said-slats,

said edges 29 the same can hence be removed. there i ng grooves in said blocks one havthrough the grindin action as the slats slide as described. he same action is also advantageous when a slight obstructionis encountered in the path of the belt, a shit having a-- very slight yielding act-ion above said obstruction without lifting the whole machine, the rigid cater illar riding upon the tops of all the large 0 structions without bouncing u and down in and over the hollows and ridges, as would be the case with an orhinarycaterpillar belt.

Fig. 6 provides another method of limiting the sliding indicated in Fig. 5. A lug 32 is attached to one end of each of clamp blocks I l-and another lug 33 to the other end of each of said clamp blocks in such a osition that when the belt is assembled eac seting a projection and the other a correspondin'gdepression, a cable passing th-rou h said grooves infthe blocks and adapted to distorted by the projection into the depression, and means for clamping the blocks to'gether upon the slats to hold the parts in place upon the cable. v

3. A traction belt for caterpillar type traction engines com rising a number. of ground-engaging mein ers, means for interconnecting said members to permit the belt to bend in one direction; and toremain in alinement against pressure in' the opposite direction, said means including overlapping pieces havin reduced portions for permitting the in 'vidual slats to have relative transverse movement when the belt is in its traction engines comprising a plurality of cables, a plurality of plates extending adjacent one another across said cables, and means for securing said plates to thecables, said securing means comprising hooks which 'overlap and coact along the line of joinder I between the plates and hold the' plates rigidly interconnected 'in a common plane against pressure in onefldirection.

6. A traction belt for caterpillar type traction engines comprising a plurality of plates extending side by side and with the edges thereof in close proximity, a rable passing over said plates adjacent each end thereof, a pair of members secured to the ends of each plate and clamping the cable between the same for flexibly securing the belt-to the cable, one of said members at the ends of each plate having hooks which overlap and coact along the line of joinder between the plates and hold the plates rigidly interconnected in a common plane against pressure 111 one direction, and the other of said members having a series of lug-receiving sockets, and sprocket driving Wheels having lugsengageable in said sockets.

In testimony whereof I aflix my signature in presence of two Witnesses.

DE VVITT NELSON.

Witnesses:

F. A. VVHITELEY, H. A. BOWMAN. 

